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Another source says just weeks ago Mateen went to Pulse nightclub, Disney Springs with wife

FBI looking into claims Mateen used gay dating apps

(CNN)Investigators believe the Orlando nightclub gunman made surveillance trips to the club and a Disney shopping complex earlier this month -- the same week Disney and other sites were hosting Gay Days 2016.

Omar Mir Seddique Mateen's visits to the Pulse gay nightclub and Disney Springs happened between June 1 and June 6, a law enforcement official said Tuesday. Gay Days 2016 celebrations took place at Walt Disney World and other Orlando locations between May 31 and June 6.

A law enforcement official said the gunman's wife, Noor Salman, went with her husband to the two locations. It's unclear how much she knew about his intentions.

Mateen had showed an aversion toward gays -- making inflammatory remarks and expressing outrage at the sight of two men kissing, law enforcement officials and a former co-worker said.

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But sources say he visited gay chat rooms and for years frequented the same nightclub that he would eventually terrorize.

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Was the mass shooting fueled by homophobia? Was the gunman struggling with his own sexuality? Or was he really inspired by ISIS, as his mid-rampage call to 911 suggests?

Authorities are investigating many angles to try to understand what prompted him to carry out the deadliest mass shooting in U.S. history. A total of 49 people were killed early Sunday and 53 people were wounded. Officials said that 28 victims are still hospitalized, including at least four people who are in critical condition.

Scouting out Disney World, Disney Springs

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Disney security officials told the FBI they believe Mateen visited Disney World on April 26 to conduct surveillance, a law enforcement official told CNN. The FBI is investigating that possibility.

Mateen's wife also was with him on the Disney World visit. Federal authorities have questioned Salman, who told them, according to a law enforcement official, that her husband had talked about a jihadist attack but she denied knowing he planned to attack the gay club.

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More than a month after that Disney World trip, Mateen and his wife visited Pulse and Disney Springs -- an entertainment and shopping complex -- apparently to scout out the locations, a law enforcement official said. Authorities believe he was conducting surveillance, based on information learned in interviews.

The early June visits took place during the same period Mateen was purchasing the weapons used in the devastating attack.

Hours before the carnage, Mateen made one last trip to Disney Springs, law enforcement officials said. That time, Mateen was alone.

Conflicting persona

Officials say they're looking into the possibility Omar Mateen radicalized on his own.

To some, Mateen was a homophobic "bigot." To others, he was a friendly regular at the nightclub.

Chris Callen, who worked at Pulse as a performer, said he had seen Mateen dozens of times. According to Callen's estimate, Mateen visited Pulse twice a month over three years.

"He was very friendly when we said, 'Hi.' He didn't seem like the kind of guy who just did what he did. It makes no sense," Callen said. "My partner said that he was very nice (and seemed) comfortable."

Mateen visited gay chat rooms online, two law enforcement officials said. Investigators do not know whether he visited the chat rooms for surveillance purposes ahead of the attack or for personal reasons.

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"He was an angry person, violent in nature, and a bigot to almost every class of person," former co-worker Dan Gilroy told CNN affiliate WPTV. Mateen and Gilroy had worked together at PGA Village in Port St. Lucie.

Gilroy said Mateen had a temper.

"He would hit things and as he was hitting things, he would yell, and of course there was always curse words involved," Gilroy told WPTV. "And this wasn't seldom, this was all the time."

And Mateen's ex-wife, Sitora Yusufiy, says he was often violent, abusive and prone to outbursts, including one instance where she was on the phone with her mother and was slapped so hard the phone broke.

As questions about Mateen's sexual orientation arise, Yusufiy admitted she does not know if he is gay or not.

"It doesn't surprise me that he might be gay. And it doesn't surprise me that he was leading two totally different lives and was in such deep conflict within himself," she said in an interview with CNN's Don Lemon. "I hope people can truly understand that this is one insane person that did such a tragic thing."

FBI had investigated him twice

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Mateen first came on the FBI's radar in 2013 when he made "inflammatory comments to co-workers alleging possible terrorist ties," Assistant Special Agent in Charge Ronald Hopper said. But investigators "were unable to verify the substance of his comments," he said.

In 2014, the FBI interviewed Mateen again over possible connections with Moner Mohammad Abu-Salha, a Florida man who became the first known American suicide bomber in Syria. The two men frequented the same mosque.

"We determined that contact was minimal and did not constitute a substantive relationship or threat at that time," Hopper said.

Mateen had worked for nine years as a security officer at G4S Secure Solutions, one of the world's largest private security companies. According to a neighbor, he was a security guard at the St. Lucie County Courthouse, often manning the metal detectors at the front of the building.

Sheriff Ken Mascara said that in 2013 his staff requested Mateen be transferred from the courthouse because he made inflammatory comments. Mateen's supervisor notified federal agents, after which, the sheriff said, the FBI investigated the guard.

Mateen told an attorney for G4S about being questioned, an official for the security company told CNN's Rene Marsh. G4S determined Mateen's comments were "exaggerated."

By that time, Mateen was working security at a retirement village. He had no reprimands in his file and had his security officer license renewed four times -- in each instance passing background checks by the state and FBI.

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After meeting with national security officials Tuesday, President Barack Obama said there is no indication a foreign terror group directed the Orlando massacre. But he conceded that "these lone actors or small cells of terrorists are very hard to detect and very hard to prevent."

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"Radicalism? No. He doesn't have a beard even. When someone becomes radical, they grow long beards and they wear clothes that you know, long clothes, and I don't think religion or Islam had nothing to do with this," he said.

He said his son may have pledged allegiance to ISIS because "he wanted to boost himself."

But the father condemned the terror group.

"The way they conduct themselves, they're harming everybody. They're not a religious group. I don't know what they are," he said. "They're a killer group."

Photos:Worst mass shootings in U.S.

Photos:Worst mass shootings in U.S.

Police direct family members away from the scene of a shooting Sunday, June 12, at the Pulse nightclub in Orlando. A gunman opened fire at the club, killing 50 people and injuring at least 53, police said. It is now the deadliest shooting rampage in U.S. history.

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In December, two shooters killed 14 people and injured 21 at the Inland Regional Center in San Bernardino, California, where employees with the county health department were attending a holiday event. The shooters, Syed Rizwan Farook and his wife Tashfeen Malik, were later killed in a shootout with authorities. The pair were found to be radicalized extremists who planned the shootings as a terror attack, investigators said.

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Police search students outside Umpqua Community College after a deadly shooting at the school in Roseburg, Oregon, in October. Nine people were killed and at least nine were injured, police said. The gunman, Chris Harper-Mercer, committed suicide after exchanging gunfire with officers, a sheriff said.

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A man kneels across the street from the historic Emanuel African Methodist Episcopal Church in Charleston, South Carolina, following a shooting in June 2015. Police say the suspect, Dylann Roof, opened fire inside the church, killing nine people. According to police, Roof confessed and told investigators he wanted to start a race war. He pleaded not guilty to 33 federal charges in July.

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Police officers walk on a rooftop at the Washington Navy Yard after a shooting rampage in the nation's capital in September 2013. At least 12 people and suspect Aaron Alexis were killed, according to authorities.

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Connecticut State Police evacuate Sandy Hook Elementary School in Newtown, Connecticut, in December 2012. Adam Lanza opened fire in the school, killing 20 children and six adults before killing himself. Police said he also shot and killed his mother in her Newtown home.

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James Holmes pleaded not guilty by reason of insanity to a July 2012 shooting at a movie theater in Aurora, Colorado. Twelve people were killed and dozens were wounded when Holmes opened fire during the midnight premiere of "The Dark Knight Rises." He was sentenced to 12 life terms plus thousands of years in prison.

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A military jury convicted Army Maj. Nidal Hasan of 13 counts of premeditated murder for a November 2009 shooting rampage at Fort Hood, Texas. Thirteen people died and 32 were injured.

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Jiverly Wong shot and killed 13 people at the American Civic Association in Binghamton, New York, before turning the gun on himself in April 2009, police said. Four other people were injured at the immigration center shooting. Wong had been taking English classes at the center.

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Pallbearers carry a casket of one of Michael McLendon's 10 victims. McLendon shot and killed his mother in her Kingston, Alabama, home, before shooting his aunt, uncle, grandparents and five more people. He shot and killed himself in Samson, Alabama, in March 2009.

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Virginia Tech student Seung-Hui Cho went on a shooting spree on the school's campus in April 2007. Cho killed two people at the West Ambler Johnston dormitory and, after chaining the doors closed, killed another 30 at Norris Hall, home to the Engineering Science and Mechanics Department. He wounded an additional 17 people before killing himself.

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Mark Barton walked into two Atlanta trading firms and fired shots in July 1999, leaving nine dead and 13 wounded, police said. Hours later, police found Barton at a gas station in Acworth, Georgia, where he pulled a gun and killed himself. The day before, Barton had bludgeoned his wife and his two children in their Stockbridge, Georgia, apartment, police said.

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Eric Harris, left, and Dylan Klebold brought guns and bombs to Columbine High School in Littleton, Colorado, in April 1999. The students gunned down 13 and wounded 23 before killing themselves.

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In October 1991, George Hennard crashed his pickup through the plate-glass window of Luby's Cafeteria in Killeen, Texas, before shooting 23 people and committing suicide.

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James Huberty shot and killed 21 people, including children, at a McDonald's in San Ysidro, California, in July 1984. A police sharpshooter killed Huberty an hour after the rampage began.

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Prison guard George Banks is led through the Luzerne County courthouse in 1985. Banks killed 13 people, including five of his children, in Wilkes-Barre, Pennsylvania, in September 1982. He was sentenced to death in 1993 and received a stay of execution in 2004. His death sentence was overturned in 2010.

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Officers in Austin, Texas, carry victims across the University of Texas campus after Charles Joseph Whitman opened fire from the school's tower, killing 16 people and wounding 30 in 1966. Police officers shot and killed Whitman, who had killed his mother and wife earlier in the day.

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Howard Unruh, a World War II veteran, shot and killed 13 of his neighbors in Camden, New Jersey, in 1949. Unruh barricaded himself in his house after the shooting. Police overpowered him the next day. He was ruled criminally insane and committed to a state mental institution.